Effects of Robot Non-Verbal Behaviors on Human Emotion Recognition in Human–Robot Communication

Abstract

Social robots are increasingly used in daily environments, where effective emotional communication is essential for smooth human–robot interaction. This study investigates whether robot non-verbal behaviors enhance human recognition of emotional content conveyed through spoken narratives.Narrative-based emotional messages representing basic emotions derived from Plutchik’s emotion wheel were constructed and validated in a preliminary experiment with 132 participants. A main experiment was then conducted with twelve adult participants. Emotional narratives were presented under two conditions: with and without robot non-verbal behaviors expressing corresponding emotions. The robot executed predefined gestures, body movements, and gaze behaviors synchronized with key emotional sentences. After each presentation, participants rated perceived emotional content using a five-point emotion recognition scale. Results showed significantly higher emotion recognition scores when robot non-verbal behaviors were present in both joy and sadness conditions. These findings indicate that appropriate robot non-verbal behaviors enhance human recognition of emotional content conveyed through spoken messages. From a human factors perspective, this study provides design implications for developing social robots that support intuitive emotional communication.

Keywords: Human–robot Interaction, Emotion Recognition, Non-verbal Behavior, Social Robots, Human Factors

DOI: 10.54941/ahfe1007680